SB2026042854 - Code Injection in Windmill

Description

This security bulletin contains information about 1 vulnerability.

1) Code Injection (CVE-ID: CVE-2026-33881)

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote user to inject arbitrary JavaScript code.

The vulnerability exists due to improper control of code generation in the NativeTS executor in backend/windmill-worker/src/worker.rs when interpolating workspace environment variable values into JavaScript string literals. A remote user can set a crafted workspace environment variable value containing a single quote to inject arbitrary JavaScript code.

The injected code executes inside every NativeTS script in the workspace as the executing user and can access reserved variables such as WM_TOKEN and WM_EMAIL.

Remediation

Install update from vendor's website.

References

• https://github.com/windmill-labs/windmill/security/advisories/GHSA-8q8j-mm3g-5c2q
• https://github.com/advisories/GHSA-8q8j-mm3g-5c2q